Since Nelson Goodman 1951, the assumption that phenomenal indiscriminability is non-transitive is taken generally for granted. Moreover, this assumption was used (by Goodman 1951, Travis 1985, Dummett 1975 and others) to argue against the existence or coherence of subjective and/or observational properties. Recently, however, the assumption has been questioned [Fara 2001] and I agree with Fara that the assumption is much more problematic than was thought, partly because it is not clear what is meant by the relation of phenomenal indiscriminability, and partly because it is not clear how to interpret ideas such as continuous change, and the limitations of our power of perceptual discrimination. In this paper I will bypass the question of the transitivity of phenomenal indiscriminability. I will use only the assumption about the existence (or even the possibility of existence) of a phenomenal sorites. This assumption is less controversial, and accepted (at least the version I will use) by opponents and defenders of transitivity alike. I will argue that the incoherence of 'red' (as response-dependent or purely observational) can be derived without committing ourselves to a view on the question of transitivity, and I will use this incoherence, to argue against the account of 'red' as a response-dependent concept.